This invention relates to battery conservation in data transmission systems.
In some circumstances the conservation of battery energy in data transmission systems becomes of importance.
A particular area where this is of concern is in the field of pipeline, and particularly downhole communications. In these situations the power demands for transmission can be relatively high compared with the capacity of batteries which can be used. Particularly in downhole circumstances, the types of batteries which can be used and the expense of these batteries is influenced by the environment in which they must survive and operate. These factors lead to it being desirable to conserve battery energy where possible. Furthermore, in the case of some installations, particularly downhole, the replacement of used batteries can be difficult, impossible or not cost effective. In some cases, when the batteries powering a tool have run down, the tool as a whole will have to be replaced.
In other circumstances it will be desired to increase the distance over which signals can be transmitted rather than prolonging battery life. Again, in these circumstances, systems which effectively conserve battery energy are useful since the power used in transmitting any one set of data might be increased to increase range without adversely affecting the life of the battery compared with a less efficient data transmission system.
It is an object of this invention to provide methods, systems and apparatus which conserve battery energy whilst transmitting data.